The O-alkylated halopyridinates corresponding to Formula I are a known class of herbicides. ##SPC1##
In I, each X is independently hydrogen or halo and at least one X is halo (i.e., fluoro, chloro, bromo or iodo); Y is hydrogen, halo or NR'R" wherein R' and R" are each independently hydrogen or lower alkyl of 1 to 4 carbon atoms; R.sub.1 is hydrogen or methyl; and R.sub.2 is lower alkyl. As used herein, the term "lower alkyl" shall mean an alkyl radical of from 1 to 4 carbon atoms (i.e., methyl, ethyl, propyl and butyl).
Compounds of Formula I have been prepared by reacting (a) an alkali metal halopyridinate corresponding to the formula ##SPC2##
Wherein M is an alkali metal and X and Y have the aforesaid meaning, with (b) a lower alkyl ester of .alpha.-chloro or bromo acetic acid (or propionic acid) corresponding to the formula ##EQU1## wherein R.sub.1 and R.sub.2 have the aforesaid meaning and R.sub.3 is chloro or bromo. The reaction has been conducted under various and miscellaneous reaction conditions and has been plagued by the low reaction rates, concurrent formation of N-alkylated by-products, and so forth.